A novel phantom is presented for 'full system' dosimetric audit comparing planned and delivered dose distributions in HDR gynaecological brachytherapy, using clinical treatment applicators. The brachytherapy applicator dosimetry test object consists of a near full-scatter water tank with applicator and film supports constructed of Solid Water, accommodating any typical cervix applicator. Film dosimeters are precisely held in four orthogonal planes bisecting the intrauterine tube, sampling dose distributions in the high risk clinical target volume, points A and B, bladder, rectum and sigmoid. The applicator position is fixed prior to CT scanning and through treatment planning and irradiation. The CT data is acquired with the applicator in a near clinical orientation to include applicator reconstruction in the system test. Gamma analysis is used to compare treatment planning system exported RTDose grid with measured multi-channel film dose maps. Results from two pilot audits are presented, using Ir-192 and Co-60 HDR sources, with a mean gamma passing rate of 98.6% using criteria of 3% local normalization and 3 mm distance to agreement (DTA). The mean DTA between prescribed dose and measured film dose at point A was 1.2 mm. The phantom was funded by IPEM and will be used for a UK national brachytherapy dosimetry audit.
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http://dx.doi.org/10.1088/0031-9155/58/19/6623 | DOI Listing |
Clin Transl Sci
January 2025
Clinical Pharmacology, Translational Medicine and Clinical Pharmacology, Boehringer-Ingelheim Pharma, Ingelheim, Germany.
Hepatic impairment (HI) trials are traditionally part of the clinical pharmacology development to assess the need for dose adaptation in people with impaired metabolic capacity due to their diseased liver. This review aimed at looking into the data from dedicated HI studies, cluster these data into various categories and connect the effect by HI with reported pharmacokinetics (PK) properties in order to identify patterns that may allow waiver, extrapolations, or adapted HI study designs. Based on a ratio ≥ 2 or ≤ 0.
View Article and Find Full Text PDFJ Clin Med
December 2024
National Laboratory Astana, Nazarbayev University, Astana 010000, Kazakhstan.
Despite the high progress that has been made in the field of cardiology, the left ventricular assist device (LVAD) can still cause complications (thrombosis/bleeding) in heart failure (HF) patients after implantation. Complications develop due to the incorrect dose of antithrombotic therapy, due to the influence of the non-physiological shear stress of the device, and also due to inherited genetic polymorphisms. Therefore, the aim of our study is to identify the influence of the genetic polymorphisms on complication development in HF patients with implanted LVADs with prescribed antiplatelet therapy.
View Article and Find Full Text PDFCancers (Basel)
January 2025
Istituto Nazionale di Fisica Nucleare, Sezione di Bari, 70125 Bari, Italy.
Background: Boron neutron capture therapy (BNCT) is an innovative binary form of radiation therapy with high selectivity towards cancer tissue based on the neutron capture reaction B(n,α)Li, consisting in the exposition of patients to neutron beams after administration of a boron compound with preferential accumulation in cancer cells. The high linear energy transfer products of the ensuing reaction deposit their energy at the cell level, sparing normal tissue. Although progress in accelerator-based BNCT has led to renewed interest in this cancer treatment modality, in vivo dose monitoring during treatment still remains not feasible and several approaches are under investigation.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
State Key Laboratory of Functions and Applications of Medicinal Plants, School of Pharmaceutical Sciences, Guizhou Medical University, Guiyang 550025, China.
Mycophenolic acid (MPA) is a commonly used immunosuppressant. In the human body, MPA is metabolized into mycophenolic acid 7-O-glucuronide (MPAG) and mycophenolic acid acyl-glucuronide (AcMPAG) mainly through liver glucuronidation, which involves UDP-glucuronosyltransferase (UGTs) and transfer proteins. Research has indicated that the pharmaceutical excipient PEG400 can impact drug processes in the body, potentially affecting the pharmacokinetics of MPA.
View Article and Find Full Text PDFInt J Radiat Oncol Biol Phys
January 2025
Institute of Biostatistics and Registry Research, Brandenburg Medical School Theodor Fontane, Neuruppin, Germany. Electronic address:
Purpose: To contrast breast radiation exposure from chest radiotherapy in 2006-2021 with 1965-1997, and to compare breast cancer (BC) risk 25 years after treatment predicted by two models.
Methods: Radiation dose distributions to the breast from 101 chest radiotherapies given 2006-2021 for Hodgkin lymphoma (HL) or other lymphoma in one German and two Dutch hospitals were compared with doses received by 505 Dutch HL patients treated 1965-1997 and sampled into a nested case-control study, weighted to represent a HL patient cohort. Dose-volume histograms, mean dose and doses to 10 breast segments were evaluated.
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